npm / lighthouse
lighthouse
What changed in lighthouse 13, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-17.
2 breaking1 security12 new APIs and options15 behavior and defaults8 fixes and other
See which of these apply to your code, ranked, in your agent:
npx @unstale/cli initlighthouse 1338 changes
Breaking changes 2
WebMCP snapshot mode was removed.
Adds a baseline compatibility audit and includes it in the default configuration, so Lighthouse runs it by default.
Security 1
Sanitizes entity homepage URLs in reports.
New APIs and options 12
Adds the Agent Resource Discovery audit.
The viewer enabled the Agentic Browsing category via the PSI API.
Adds evaluateOnObject to ExecutionContext for evaluating on an object.
Lighthouse now provides a public types entrypoint for importing its types.
A new agentic browsing category is added to the default config.
Adds a new agentic browsing category, with accessibility audits enabled and aggregated for the category.
Adds an llms.txt check for AI agents and refines its validation logic.
Adds an audit for missing WebMCP tool annotations.
Adds an audit that lists registered WebMCP tools.
Adds an audit that checks for WebMCP schema issues.
Adds a WebDX feature usage trace category.
The robots-txt audit now supports the Content-Signal directive.
Behavior and default changes 15
Groups the llms.txt and ARD audits under agent discovery.
User flows can abort pending navigations.
Plugin category validation is centralized and enforced.
Plugin versions are included in LHR credits.
Displays plugins in the report footer.
Warns when the recommended limit is exceeded.
WebMCP gatherers now check document.modelContext.
Improved Dynamic Baseline High calculation and feature summaries, affecting the baseline results Lighthouse reports.
Lighthouse now provides detailed error messages when fetching llms.txt fails.
Lighthouse now provides detailed error messages when fetching robots.txt fails.
Moves specific accessibility audits into the default configuration.
Adjusts how WebMCP audits behave when WebMCP is unsupported.
The baseline audit report now includes baseline icons.
Reverts strict wrapping of network requests, changing how Lighthouse handles those requests.
The valid language list used for hreflang checks was updated, which may affect Lighthouse audit results.
Fixes and other changes 8
Passes instead of reporting n/a when all forms are covered.
Validation for invalid URLs in the canonical audit has been improved.
The header check now allows leading whitespace.
Implements a UKM Invalidate fallback for LCP.
The baseline audit description now includes the web-feature version.
Fixed focus behavior in DevTools and its three-dot menu.
Fixed tooltip positioning in DevTools.
Fixed the incorrect DPR used for responsive images advice.